Electrochemical test systems based on the principle of electrochemical biosensor are widely used in the field of point-care-of-testing (POCT). Usually, electrochemical test systems comprise an electrochemical test strip and an electrochemical instrument. The biological molecules (such as enzyme) modified on the electrode of test strip can selectively identify the target analytes of the test sample, and the biorecognition signals are transformed into electrical signals (e.g., oxidation or reduction current) during this process. Then the electrochemical instrument can collect and measure the electrical signals to quantitatively detect the target analytes. Electrochemical test systems of this type can be used to detect a variety of disease markers in the blood, and is of significance to the prevention and adjuvant treatment for related diseases.
Generally, in order to ensure the reliability and accuracy of an electrochemical test system, quality control of such a system should be carried out regularly to determine whether the test system can work properly. For instance, the common blood glucose test system is equipped with blood glucose quality control liquid, the operator needs to measure blood glucose quality control liquid on blood glucose test system at regular intervals. If the measured value exceeds the concentration range of blood glucose quality control liquid, the result indicates the reduced reliability of blood glucose test system, thus the blood glucose test system can not be used for clinical detection.
The common quality control mode of electrochemical test system for an operator is to manually select the quality control measurement mode on the test system, then installing an electrochemical test strip in the electrochemical instrument. Quality control measurement can be achieved by supplying quality control liquid to the electrochemical test strip. In this mode of operation, the operator will need to manually switch measurement mode between quality control measurement and real sample (such as blood) measurement. If the operator measures the real sample on the test system under the quality control measurement mode, or measures the quality control liquid on the test system under the real sample measurement mode, it will give a risk of inaccurate test results, and can not guide the operator to make a correctly clinical judgment. So it is highly desirable to develop a method to automatically distinguish between quality control liquid and real sample in an electrochemical test system, which is of great significance to simplify the operation steps of quality control, avoid the misoperation under manual quality control mode, and improve the accuracy and reliability of measurement results.